It is known in the art to secure metal foil seals to the cap of a container by passing the cap with the metal foil seal seated on it through a magnetic field generated by applying a high frequency current to an inductor coil. The magnetic field inductively heats the metal foil, which in turn heats and cures a sealing material adhering to the foil. The sealing material, typically a thermoplastic resin, sets and seals to the lip of the container's opening. Known foil cap sealers have components that require water cooling and/or forced air cooling. For example, the inductor could be a hollow copper tubing or bus bar that is cooled by running water through the hollow passage of the tubing or bus bar. The use of Litz wire, which is known in the art, reduced heat losses to the extent that forced conduction air cooling of the foil cap sealer became feasible. Forced conduction air cooling, with the requirement for one or more typically electrically driven fans, requires additional energy consumption and increases the volume and weight of the foil cap sealing equipment.
Additionally, foil cap sealers known in the art consist of a unitary enclosure that includes the sealing head and a high frequency power supply. The unitary enclosure must be supported and suspended over a processing line that transports the caps of the containers under the sealing head to heat the foil seals. This arrangement substantially increases the weight that must be supported over the processing line. Additionally, failure in the power supply or failure in the sealing head will necessitate the replacement of the entire foil cap sealer's unitary enclosure.
Therefore, there exists the need for a modular air-cooled, energy efficient induction cap sealer that will not require forced air or water cooling.